Bruce Dern said that Burt Lancaster's wife arrived on the set while her husband openly showed a relationship with his mistress Jackie Bone, one of the crew members.
The castle set in Yugoslavia blew up and burned to the ground. It was quite a surprise to the cast and crew. Sydney Pollack immediately grabbed the camera and shot what he could of the burning castle.
In some scenes in the film, including the climactic battle at the castle, Major Falconer wears a tan "jump suit" jacket and pants uniform, usually only issued to paratroopers.
Sidney Pollack confessed that the shooting took too long to complete, which meant that warm weather began to melt the snow. The crew also became very erratic because of this shooting where actors had to act in hot summer as if it were in deep winter.